The posts are displayed no problem. But this is where I get lost. If the 'body' copy is longer than, let's say, 30 words (which all of the posts are), I'd like it to be truncated and replaced with '... Read more >" You get the idea.

I've found a few examples online (unrelated to tumblr embedding) but the code is so detailed and interwoven, and me being the newbie that I am, I don't know which bits I need and which I don't.

Could someone point me in the right direction, given the code that I already have?